Each vehicle in the line has a unique body shell structure, adapted to the body of the vehicle, the vehicle's propulsion mode and/or the equipment supported by said body shell.
FIG. 1 shows, from the inside of the vehicle, a vehicle body shell 2 of the prior art according to a first configuration.
In this first configuration, the body shell 2 comprises an instrument panel crossmember 4 extending transversely in the vehicle, and the ends of which are respectively fixed on the right and left front pillars of the body structure, by means of a support 6.
Traditionally, the crossmember 4 is formed by a hollow tubular element.
The crossmember 4 is designed to support different equipment of the vehicle, such as the instrument panel (not shown) of the vehicle. It may also serve to support a steering column support 8 of the vehicle.
To that end, the crossmember 4 comprises different support tabs (not shown) designed to support different pieces of equipment of the vehicle.
As shown in FIG. 1, the body shell 2 comprises an upper fire wall 10 separating the engine compartment of the vehicle and the passenger compartment 12 of that vehicle, and a lower recess crossmember 14 situated below the windshield of the vehicle, said upper fire wall 10 and said lower recess crossmember 14 being situated substantially at the instrument panel crossmember 4. A floor 16 delimits the bottom part of the passenger compartment 12.
A connecting tab 18, extending substantially in the longitudinal direction X of the vehicle, connects the lower recess crossmember 14 and the instrument panel crossmember 4.
The vehicle body shell made according to this first configuration also comprises a strut 20 connecting the main body of said crossmember 4 and the floor 16, to react part of the forces borne by the crossmember 4 and transmit them to the structure of the vehicle via the floor 16. The strut 20 is situated near the steering column support 8.
Other vehicle body shells exist that are made according to a second configuration. These vehicle body shells only comprise a half-crossmember of an instrument panel, i.e., only a single crossmember portion situated across from the driving seat and suitable for receiving the steering column support. In this second configuration, one of the ends of the portion is fixed to the left front pillar, and the other end supports the upper end of the strut. Thus, in this configuration, the forces borne by the crossmember are transmitted to the front left pillar and the floor.
Vehicle body shells also exist made according to a third configuration. These vehicle body shells do not comprise any strut, the forces borne by the crossmember extending transversely in the vehicle then being transmitted only to the structure of the vehicle via the right and left front pillars.
The different configurations described above may each be developed for a different type of vehicle, for example a sedan, a coupe, a coupe/cabriolet, etc., or for vehicles having different propulsion modes, such as an internal combustion engine, an electric engine or a hybrid propulsion mode.
Likewise, these different configurations may be used for vehicles having different equipment or for vehicles intended to be sold in different geographical regions. In fact, from one country to another, the safety standards vary, which sometimes requires redeveloping the body shell of the vehicle.
However, the development of each new vehicle body shell is expensive. A design study must be conducted on the body shell and, in particular, its instrument panel crossmember and any strut that may be present each time. Furthermore, each new development of parts requires expensive specific tools.